1. Field of the Invention
This invention relates to novel guanidinobenzoic acid derivatives and process for their preparation.
2. Description of the Prior Art
A number of compounds are known to have anti-plasmin and anti-trypsin activities. For example, trans-4-aminomethylcyclohexanecarboxylic acid as disclosed in S. Okamoto and U. Okamoto, Keio Journal of Medicine, 11, 105 (1962) is known to be an anti-plasmin agent. "Trasylol" as described in B. Kassel et al, J. Biol. Chem., 238, 3274 (1963) and German Patent Application (OLS) No. 1,905,813 is known to be an anti-trypsin agent, and the compounds disclosed in U.S. Pat. No. 4,021,472 are known to be both an anti-plasmin agent and an anti-trypsin agent.
However, trans-4-aminomethylcyclohexanecarboxylic acid and Trasylol have disadvantages because they exhibit relatively low activities. The compounds described in U.S. Pat. No. 4,021,472 provide the same anti-plasmin or anti-trypsin effect at a lower dosage level than can be achieved with trans-4-aminomethylcyclohexanecarboxylic acid and trasylol. However, there has been an increasing demand for compounds even more potent at a lower dosage level since reduced dosage generally means lowered side effects which is desirable from the standpoint of safety.